You guys expect it will take a long time before this game is finished?
How should anybody know? Recent updates came about three times a year, plus minor updated in between. How many updates are to come, who knows? There are plans for the next couple of updates, though, but I guess even DC does not know what stories he wants to tell.
I think at some point he even mentioned that once the Summerville stories are finished, he might expand the game universe, e.g. by introducing more maps (cities). So the game might potentially never be finished at all. But personally I think this would mean several games instead of further expanding this one.
On the other hand -- who knows what the patreons will do if the game is finished, and the new project starts at Zero? So perhaps he starts the sequel while the current game is still unfinished. As I said, who knows?